Pope Pius IX and the United States
The relationship between Pope Pius IX and the United States was an important aspect of the pontiff's foreign policy and Church growth program.
Period of steady immigration
Together with German and Italian immigrants, the Catholic population in the United States increased from 4 percent at the beginning of the pontificate of Pius IX in 1846 to 11 percent in 1870. Some 700 priests existed in the U.S. in 1846 compared to 6000 in 1878. Pope Pius IX contributed to this development by establishing new Church regions and the installation of capable American bishops.
Creation of modern ecclesiastical structures
Pius IX is the father of much of the modern American church structure by creating many existing dioceses and archdioceses in the U.S. such as the Roman Catholic Dioceses of Portland, Springfield, Illinois, Burlington, Cleveland, Columbus, Galveston-Houston, Providence, Fort Wayne-South Bend, Kansas City in Kansas, Saint Paul and Minneapolis, San Francisco, Seattle, San Antonio and others. Some of his creations do not exist anymore: On 24 July 1846, Pius IX divided the existing Oregon vicariate apostolic into three dioceses: Oregon City (Oregonopolitanus); Walla Walla (Valle Valliensis); and Vancouver Island (Insula Vancouver).
New sees in the Western states
On 29 July 1850, the Diocese of Oregon City was elevated to an archdiocese with Archbishop Blanchet continuing to serve as its first archbishop. In 1850, Pius IX erected seats at Monterey and Santa Fe in the Spanish-Mexican territories recently added to the United States and in Savannah, Wheeling, and Nesqually, and made the Indian Territory a vicariate under a bishop.
Support for synods and meetings
Pius IX supported Diocesan synods and regular meetings, and granted all wishes of the American bishops regarding enlargements of their rights and privileges. In 1849, from his exile in Gaeta, he politely turned down an invitation to visit the U.S. He wrote, "...nothing could afford us more pleasure, nothing could be more grateful to our hearts than to enjoy the presence and conversation of yourself and the venerable brethren ... but in the existing times and circumstances, it would be impossible for us to comply with your invitation, as your wisdom will easily understand".
The enormous growth of the Catholic Church in the U.S. and the genuine admiration in the early years for his liberal pontificate resulted in the United States establishing diplomatic relations with the Papal States on 7 April 1848. This lasted until 1867, when domestic pressures forced a closing of relations. The Vatican never had an ambassador in Washington, because the U.S. government refused to accept a Catholic priest as papal nuncio.
Pius IX pushed for an American College in Rome for future American priests and promised his personal financial support. A small college was founded in 1859 under Rev John McCloskey; it was greatly expanded under Pius XII in 1956.
Political involvement during the Civil War
During the American Civil War, Catholics oriented themselves to John Hughes (the Archbishop of New York) in the Union and to Jean-Marie Odin (the Archbishop of New Orleans) in the Confederate States. Abraham Lincoln asked Pope Pius IX to elevate Hughes into the College of Cardinals, but Pius declined to do so. A decade later, Pius did elevate John McCloskey, Hughes's successor, to the College of Cardinals.
Although Pope Pius IX never signed an actual statement supporting the Confederacy, he responded to a letter written by Jefferson Davis on 23 September 1863 with a letter to Davis written 3 December 1863. Pius's "letter to Jefferson Davis was accompanied by an autographed picture of the pope" in which the Pope addressed the Confederate President as "the "Honorable President of the Confederate States of America". This simple courtesy, though it had no legal effect, has been seized upon by some to claim that it showed that the Pope recognized (at least on a personal level) the Confederate States of America to be an actual country (and separate from the United States). In fact, no diplomatic relations or recognitions were extended in either direction. But this letter caused Congress to, in 1867, explicitly ban diplomatic ties with the Vatican.
Charles Chiniquy vowed that that letter caused great distress to the president. Robert E. Lee, pointing to his own portrait of Pius IX, told a visitor after the war that he was "the only sovereign... in Europe who recognized our poor Confederacy".
The letter was delivered to the Pope by Davis's commmissioner to Belgium, Ambrose Dudley Mann. During his visit with the Pope, Mann discussed the successful recruitment efforts by the Union who were recruiting thousands of soldiers from Ireland and Belgium, both Catholic countries. According to Clement Eaton, "Mann persuaded the Pope to discourage this enlistment of Catholics in Europe." 
- Franzen 364
- Schmidlin 207
- Schmidlin 208
- Shea 206
- Shea 171–172
- Schmidlin 211
- Schmidlin 210-211
- Schmidlin 210
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